Burglar-alarm system



(No Model.)

A. STROMBERG.

BURGLAR ALARM SYSTEM. No. 499,261;

Patented June 13, 1893.;

NORRIS PETERS co. PHo'm-umu, WASHI or other substance.

UNITED STATES PATENT OFFICE.

ALFRED STROMBERG, OFOHICAGO, ILLINOIS.

BU RG LAR-ALARM SYSTEM.

SPECIFICATION forming part of Letters Patent No. 499,261, dated June 13, 1893.

Application filed February 11, 1893. Serial No. 461,959. (No model.)

To all whom it may concern.-

Be it known that I, ALFRED STROMBERG, a citizen of the United States, residing at Ohicago, in the county of Cook and State of Illinois, have invented a certain new and useful ImprovementinBurglar-Alarm Systems,(0ase No. 8,) of which the following is a full, clear, concise, and exactdescription,reference being had to the accompanying drawings, forming a part of this specification.

My-invention relates to burglar alarm protection for windows, doors, and other openings.

In Patent No. 484,761 I have shown and described a covering for such openings wherein a curtain was employed provided with sets of line wires woven throughout the material of the curtain in the form of a net work. To,

the lower part of the curtain were attached contact devicesadapted to close the circuit through these sets of fine wire when the curtain should be closed over the opening.-

When the circuit is thus closed, if the curtain should become punctured or torn the circuit would become broken or the sides thereof crossed, thereby sending in an alarm. I mounted the curtain therein employed upon an ordinary wooden roller. I used one of the bearings of said rollers as a means for electrically connecting one of the fine wire sets to ground, while the otherpbearing I used to connect the other of said sets through the central station apparatus to ground. I have found great difficulty in making perfect electrical connections with these bearings.

It is the object of my present invention to provide a roller Whereon the flexible covering may be mounted and electrical connection between the two fine wire sets of conductors upon said curtain may readily be had and maintained with the bearings. To this end I employ a roller made up of two metal tubes connected together by an insulator of wood At the ends of these tubes are provided ordinary bearings. To each of these tubes may be easily soldered a terminal of each of the sets of fine wire upon the curtain. Electrical connection is had between these tubes and their bearings as hereinafter described.

My invention will be more readily understood by reference to the accompanyingdrawings, in which- Figure 1 is a front view of a curtain mounted upon the form of roller I employ, with a diagrammatic illustration of the electrical circuits. Fig. 2 shows a manner of arranging the curtain within a cabinet. Fig. 3 shows another manner of arranging the curtain within a cabinet. Fig. 4 is a front elevation of the roller which I employ, with parts broken away to reveal its construction. Fig. 5 is an enlarged end View of the roller shown in Fig. 4. Fig. 6 is an enlarged'end View of a modified form of roller. Fig. 7 is an enlarged front view of an end of the roller shown in Fig. 6, showing a means of making electrical contact between the metal tube and one hearing. Fig. 8 is an enlarged front view of an end of the roller shown in Figs. 4 and 5, showing another means of making electrical contact between the metal tube and one bearing.

Like parts are indicated by similar letters of reference throughout all of the views.

The curtain is mounted upon' a roller 0.

which is composed of two metal tubes b c which are connected together by means of a plug 01 which may be made of wood, woodpulp, or other insulating material. The metal tubes are slightly separated, as shown. The relative sizes of the tubes which I have shown in the drawingsI consider preferable, although not essential. One end of one set of fine wire conductors is soldered to tube 1), while one end of the other set is soldered to the tube a. The metal bearing e is in direct electrical contact with tube I), while bearing f is put into electrical connection with tube 0 by either of the means shown in Figs. 7 and 8.

In Figs. 4, 5 and 8 I have shown a roller with the tube 0 provided with a metal end g, to which is soldered a journal h adapted to rest in bearing f. Upon bearing f I mounta contact device 2', which is made preferably in the form of a brush, which bears constantly upon the metal end g.

In Figs. 6 and 7 I have shown the roller without the metal end 9. The plug d supports the journal it directly. Upon the tube 0 I mount a contact device 11 which is in con-' stant contact with the metal plate f.

I will now describe the electrical circuit which results when the curtain has been fully drawn over the opening. Beginning with the source Z the current passes through the central station recording apparatus described in Patent No. 483,7 28, to manual switch m, thence to bearing f and by contact device '5 to the metal tube 0, thence through one set of fine wire conductors n to spring catch at and resistance 0, thence by spring catch 1) through the other set of fine Wire (1 to the metal tube 19, bearin g e, thence to ground and back to the source Z.

In Figs. 2 and 3 I have shown methods of arranging the curtain within a cabinet. To properly guide the curtain within the slots in the sides of the opening I have found it convenient to mount the roller some distance back from the slots, as shown, and cause the curtain to pass over a bearing roller 19', as shown in Fig. 2. This bearing roller I preferably make long enough to support the curtain throughout its entire width.

In place of the roller 19 there may be employed a fixed piece .9 with the surface opposing the curtain slightly curved.

I do not wish to limit myself to the precise form of roller shown, nor to the manner of making electrical connection between the same and the bearings.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In a burglar alarm protection, the combination with a roller made up of two metal tubes insulated from each other, a flexible covering mounted upon said roller, a circuit carried by said covering, each of two terminals whereof is attached to one of the said metal tubes, substantially as described.

2. In a burglar alarm protection, the combination with a roller made up of two metal parts insulated from each other, a brush mounted upon one of said parts and adapted to make contact with a contact plate, while the other of said parts is in direct electrical connection with the other bearing, one circuit wire leading from one of said bearings to ground, another circuit wire leading from the other of said bearings through a central station recording apparatus and battery to ground, a flexible covering mounted upon said roller,a circuit carried by said covering, each of two terminals whereof is attached to one of the said metal parts, substantially as described.

3. In a burglar alarm protection, the combination with a roller made up of two metal parts insulated from each other, a contact device adapted to make electrical connection between one of said metal parts and a bearing, while the other of said parts is in direct electrical connection with the other bearing, one circuit wire leading from one of said bearings to ground, another circuit wire leading from the other of said bearin gs through a central station recording apparatus and battery to ground, a flexible covering mounted upon said roller, a circuit carried by said flexible covering, each of two terminals. whereof is attached to one of the said metal parts, substantially as described.

In witness whereof I hereunto subscribe my name this 7th day of February, A. D. 1893.

ALFRED STROMBERG. VVituesses:

GEORGE W. MOll/IAHON, GEORGE L. CRAGG. 

